how to find continuous subset from given set of integers?

How can we find all possible CONTINUOUS subset from a given subset?
eg:
a =[1,2,3]

desired output: [1,2,3,12,23,123]

P.S. Null is not required. Also, can I have python implementation?

Its called subarrays. Google how to generate all subarrays.

EDIT-

Link- http://www.geeksforgeeks.org/subarraysubstring-vs-subsequence-and-programs-to-generate-them/

Thanks for that!

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